U.S. Pat. No. 3,110,633 issued in the name of W. D. Bachmann discloses a heating system for a vehicle battery; the aim of the heating system is to increase the electrical output of the battery to effective levels during start-up of the vehicle at low ambient temperatures, for example sub-zero temperatures. The patented system is constructed so that heat energy from a remote source is directed to the space immediately surrounding the battery; alternately the heat is stored within a fusible substance surrounding the battery. The requirement for an external heat source (such as a domestic hot water supply or electric power from a building or generator) presents certain disadvantages and difficulties. For example the vehicle must be located relatively close to the external heat source, not miles or fractions of miles as might be the case with military vehicles operating in arctic atmospheres over enemy terrain where location of power facilities might be unknown or non-existent. Use of a stored heat source is not entirely satisfactory when the vehicle is left unattended for a prolonged time period; the heat leaks away so that it is not available when needed.
The present invention proposes a battery-heating system wherein the heat energy is developed by catalytic heaters of the hand-warmer type. Such heaters have their own fuel supply. They develop relatively low temperature glows in the neighborhood of 500.degree. F at the catalyst as compared to 2000.degree. F open flame temperature; therefore the catalytic heater is not likely to destruct the battery casing. The relatively low glow temperatures consume the fuel (e.g. lighter fluid or unleaded gasoline) at low rates so that a given capacity (size) fuel reservoir will keep the burner going for an extended period of time. The catalytic burner can thereby be put into operation when the military vehicle is initially stopped, e.g. at the end of the day; the burner will remain on during the night so that the battery is at a relatively elevated temperature (suitable for delivering maximum electrical energy) the next morning. The catalytic burner requires no connection to an electric current source; therefore the burner can be used in wilderness areas where stationary electric power sources may be non-existent or temporarily interrupted.